/*******************************************************************************
 * Copyright (c) 2004, 2005 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package com.architexa.org.eclipse.gef.ui.actions;

import com.architexa.org.eclipse.gef.GraphicalViewer;
import com.architexa.org.eclipse.gef.internal.GEFMessages;
import com.architexa.org.eclipse.gef.rulers.RulerProvider;

import org.eclipse.jface.action.Action;


/**
 * An action that toggles the ruler {@link
 * com.architexa.org.eclipse.gef.rulers.RulerProvider#PROPERTY_RULER_VISIBILITY visibility} property
 * on the given viewer.  This action can handle the case where that property is not
 * set on the viewer initially.
 * 
 * @author Pratik Shah
 * @since 3.0
 */
public class ToggleRulerVisibilityAction
	extends Action 
{

/**
 * The viewer whose ruler visibility property is to be toggled
 */
protected GraphicalViewer diagramViewer;
	
/**
 * Constructor
 * @param	diagramViewer	the viewer whose ruler visibility property is to be toggled
 */
public ToggleRulerVisibilityAction(GraphicalViewer diagramViewer) {
	super(GEFMessages.ToggleRulerVisibility_Label, AS_CHECK_BOX);
	this.diagramViewer = diagramViewer;
	setToolTipText(GEFMessages.ToggleRulerVisibility_Tooltip);
	setId(GEFActionConstants.TOGGLE_RULER_VISIBILITY);
	setActionDefinitionId(GEFActionConstants.TOGGLE_RULER_VISIBILITY);
	setChecked(isChecked());
}

/**
 * @see org.eclipse.jface.action.IAction#isChecked()
 */
public boolean isChecked() {
	Boolean val = ((Boolean)diagramViewer
			.getProperty(RulerProvider.PROPERTY_RULER_VISIBILITY));
	if (val != null)
		return val.booleanValue();
	return false;
}

/**
 * @see org.eclipse.jface.action.IAction#run()
 */
public void run() {
	diagramViewer.setProperty(
			RulerProvider.PROPERTY_RULER_VISIBILITY, new Boolean(!isChecked()));
}

}
